Arthritis is recognized as the most common chronic condition affecting elderly persons and the leading cause of functional limitations in die United States. The number of people with arthritis in the United States is projected to increase 56.5% by the year 2020 and the number with attributable limitations is projected to increase 66.3% from their 1990 levels. Current knowledge to deal with the oncoming health care burden from this rapidly growing arthritic population is needed. This study addresses arthritis from a public health and public policy perspective by estimating differences in prevalence and incidence of arthritis and self-reported functional limitations across different ethnic/racial groups using data from the combined 1998-2002 Asset and Health Dynamics Among the Oldest Old (AHEAD) and Health and Retirement Survey (HRS). Our research will estimate the extent that these ethnic/racial differences in older adults are associated with disparities in socioeconomic status (SES), health behaviors, and access to medical care. In addition, this project evaluates differences due to SES in medical utilization among people with arthritis. The 1998-2000 AHEAD/HRS data will be augmented with Medicare records to provide documented health care utilization data. State of the art statistical methods for longitudinal data will be applied. The investigators provide a spectrum of statistical, economic, clinical, and public health expertise needed to complete this methodologically sophisticated project. The project extends their preliminary work based on the 1993 AHEAD data. This study addresses goals from Healthy People 2010 and the National Arthritis Action Plan (NAAP) related to the elimination of health disparities that occur by gender, race, education or income and the use of longitudinal databases to identify risk factors to reduce the disability from arthritis. Results from this study will serve as a benchmark against which to judge the action of the NAAP and other programs that are aimed at reducing the impact of arthritis in the population. In addition, study findings will help to identify disparities due to race/ethnicity and SES factors in the burden of arthritis and related functional limitations and medical utilization, and thereby possibly lead to improved quality of care for under-served groups.